Study: Automatic Braking Cuts Rear-End Crashes 39%

Safety systems that automatically apply the brakes to avoid a collision can reduce rear-end crashes in the U.S. by 39%, according to the Insurance Institute for Highway Safety.

IIHS figures about 700,000 rear-end collisions could have been avoided in 2013 if all cars had so-called auto-brake technology on board. The systems—which use radar, laser and/or vision sensors to monitor vehicles ahead—lower the ratio of rear-end crashes that result in injury by about 42%, according to the institute.

The analysis also estimates a 23% reduction in rear-end crashes for cars equipped with simpler systems that warn the driver about an impending crash but don’t brake the car automatically. It cautions that the simpler technology has a negligible effect on injury rates.

The National Highway Traffic Safety Administration, which began evaluating automatic braking systems three years ago, announced a year ago that it intends to require the technology beginning in the 2018 model year.

IIHS bases its findings on a study of police-reported rear-end crashes in 22 states between 2010 and 2014. The institute compared crash data for Acura, Honda, Mercedes-Benz, Subaru and Volvo models with and without front-crash systems.

The report says the most effective auto-brake option currently on the market is the Volvo City Safety system, the latest version of which operates at speeds as great as 30 mph. IIHS calculates about 25% of 2015 model vehicles sold in the U.S. offer some form of automatic braking as an option. But the feature is standard on just 1% of new vehicles.